The amount of time it takes to encrypt/decrypt is a function of the amount of data involved, obviously. Processing large files takes time.
The standard GUI interface to gnupg is call
gpa - the
Gnu Privacy Assistant.
You'll need to install
gpa (it's in the
Fedora Extras repository), if you don't already have it:
yum -y install gpa or
rpm -Uvh gpa-x.y.z.rpm
Once you have the prerequisite, the easiest way to encrypt a directory:
1. In Nautilus, right click on the directory and select "Create archive". This will create a "directoryname.tar.gz" file.
2. From the Applications->Accessories menu, run GPA. Your existing gnupg key(s) will show up. Click on the "Files" button, and in the Files window, click on the "Open" button to select the "directoryname.tar.gz" file. Click on the "Encrypt" button. If you are going to email the encrypted file, make sure you select the "Armor" checkbox.
To decrypt, reverse the process.
If you don't already have a key, you can create a new one from the gpa "Keys" menu.